Facebook's clinical trial

Social networking site Facebook made users emotional lab rats, manipulating news feeds of 689,000 accounts to assess whether positive postings trigger positive posts and an upbeat frame of mind and whether negative posts do just the opposite.

The problem: critics argue that users were unwitting participants since the posts just happened without explicit consent before the test started. Facebook argues that the user agreement indicates signing up includes agreeing to its research activities. This consent clause does not sit well with everyone. Study editor Susan Fiske tells the Guardian “People are supposed to be told they are going to be participating in research and then agree to it and have the option to not agree to it without penalty.”

Researchers published the results in Proceedings of the National Academy of Sciences. Facebook tells the Guardian that the study was intended "to improve our services and to make the content people see on Facebook as relevant and engaging as possible.”

Blue State Digital's co-founder Clay Johnson called the experiment “terrifying” in a Twitter post, which was part of a series of Tweets the Guardian reports asked "Could the CIA incite revolution in Sudan by pressuring Facebook to promote discontent? Should that be legal? Could Mark Zuckerberg swing an election by promoting Upworthy [a website aggregating viral content] posts two weeks beforehand? Should that be legal?”